Work-setting means for gear-generating machines



Mar 15 1927.

ch E. R. F ELL.ows.

woRK SETTING MEANS FORYGEAR GENE-RATNG MACHINES March 15' 1927-- E, R.FELLowS vWORK SETTING MEANS FOR GEAR GENERATING MACHIES ned Jan. 27.192:5' 'f sheets-sheet 2 lll.

March 1 1,5, 1927.

E. R. FELLOWS WORK SETTING MEANS FOR GEAR GLNmATINGl MACHINES 7Sheets-Sheet 3 Filed Jan.` 27. 1923 March Y15, 19.27'.

vE. R. Fr:| ows WORK SETTING MEANS FOR GEAR GENERATING MACHINES 7Sheets-Sheet 4 3 2 9 1 7 2 n a J d March- 15, V1927- E. R. FELLws v WORKSETTING MEANS FOR GEAR GENERAATING MACHINES I Filed Jan.27. 1923 '7Sheets-Sheet 5 March f15.- 1927.

` 1,620,811 E. R. FlLLows` l WORK SETTING MEANS FOR GEAR GENERATINGMACHINES piled Jan. 2v. 1925 '7 Sheets-Sheet New o@ l 1,620, 11 March15, 192v7. E. R. FEI-LOWS S 8 WORK SETTING MEANS FOR GEAR GENERATINGMACHINES Filed Jan. 27. 1925 7 Sheets-Shet '7 c. V.) y

Le ma v' WN tm ma y bg f @www `Patented Mar. 15, 1927. l

EDWIN 14. FELLoW-s; ,0E srmermrd, im'lvmlsfnz Agslflmn mQfmnE-FnnpowsGEAR Same 'tune @eine ah Cil i ce

shown in Figure 10 as seen from the View point of that figure, butrepresenting the parts in a diiferent position.

- Figure 12 is a planview of a partV of the means for initially settingthe work.

Figure 13 is a plan of another part of the same means containing a gageon a different partof the machine.

Figure l141- is a section on line 1& 14 of Figure 13.

Figure 15 is a cross section on line 15-15 ofFigure 3, showing a detailof mechanism.

, Like reference characters designate the same partswherever they occurin all the figures.k

The machine here represented is designed for iinishing previously shapedspur gears by a grindingoperation, and is generally,

except for the parts. and features novel with` thel present invention,substantially thesanie as the machine disclosed in my prior applicationfor Letters Patent of the United. States Serial No. 595,304filed October18,

1922, and entitled Automatic gear generating machine. It also containsmany of Y the characteristic features shown in my preceding applicationfor vLetters Patentof the UnitedStates Serial No. 578,288 filed July 29,1922,v and entitled Gear grinding 'machine. Only so much of the machineas is necessary to an explanation of the present invention is shown anddescribed in this, specification, and for explanation of details notherein shown attention is directed to the said prior applications.

The base l ofthe machine is provided with an inclined guideway 2. onwhich'is` complemental abutment 11 which Ivcall a former abutment.7 Acombination of rotation about its axis and of translation perpendicularto its axis and parallel to the guideway 2 is given to the work` piece,

' whereby the latter is caused to'roll past the grinding wheel, `and thecharacter of the rolling movement of the work is determined by theformofthefaces 9 and 10 of the former and Vabutment, respectively. .The

-former isv removable and interchangeable with others havingspecifically different .lengths locations, or'forms of the face 9 to beused with specifically diiierent` gear blanks. Normally the abutment isstationary,-having no other motions than the admesh with a rack.

(Fie

effected by turning justinents presently described, and its end facelOhas the relation tothe former 9 of a rack tooth face to that oiacomplemental gear tooth face. Of the grinding Wheel the face 12, iii. aplane perpendicular to its axis, is the part which acts on the work, andits relation to the teeth of the gear blank is that of a rack tooth faceat the opposite side of a tooth space from they tooth yto whichtheabutment 11 corresponds. f

Ai" cani 13 shown in dotted lines in Figure v1,k and also shown inFigure 3, imparts movement to the `work spindle and former through themedium of a'bell crank lever le, a second lever 15, and a rack bar 16.The lever 14 has two arms, one of which carries a roll 17 bearing on thecam 13 ,andy the other arm 18 of which bears on a roll v19` carried bythe lever 15.r The rack bar 16 is pivoted to the leverl 15 and A hasteeth which mesh with the gear 7. Thus when the ris- 'ing part of thecam passes the roll 17 the ygear 7 and former' 8 are turned inanticlockwise rotation, as seen in Figure 1, and. the pull of the rack`bar combined with the reaction oi the former. against its y, abutment11 causes the .work carriage ytobe Inoved upward and to the left (Figure1- `to the right, Figure 2).

The rotary motion given to the work spindle yis that permitted to theformer relatively to the abutment; and the compound movement of rotationand translation,.both

fof the former tothe abutment and of the work piece to the grindingwheel, is equivalent to that of a gear wheel rolling in gear blank aregenerated accuratelyfto a prescribed forni, controlled by the faces ofthe lformer `and its abutment, .at the same time that they are cut awayto required siae by the action of the grinding wheel. Cutting takesplace mainly on the upward travel of the work; and at the end of theldownward travel, Awhich is effected by gravity, with aid from a springif desired, the work is indexed in order to bring another tooth v intopositionv yto be cut on the `next upward travel. Operative means forconnecting the former to the Work spindle and for indexing the work, aswell as means tor Thus the teeth of the mounting and adjusting thegrinding wheel,

and the relation of the grinding wheel in all aspects, are fullyillustrated in inyprior application Serial No. 578,288 aforesaid.

In order to remove all of the Istock necessary to bring the work toiinished size,vseveral successive cuts on each tooth are required. .lprefer to feed the work piece for each next deeper cut after a precedingseries et cuts or" equal depth have been taken lon all of the teeth.

the work spindleslightly about its axis before beginning a sub- Feedingof the work is i ao . the ratchet teeth. On the outervface of the gear67are secured a number of detach` able cam segments `73 r(shown in Figures4and 7 the function of which is to reciprocate the' rack 40 whenevergear'66 is turned. These cam segments when all in place formv a completecam of five lobes;

i "ff and they are made detachable in order that psegments havingvgreater orless lift, or no lift, may be substituted'4 for one another.lt will be noted in Figure 4 that these cam segments have no risewhatever in Vhalf of their angular length, and that their whole rise is`limited to the-remaining half. This construction is provided to rpermitalternate ysteps rof the cam being taken without affecting the workfeeding mechanism and to cause the intermediate steps only of the cam tooperate'this mechanism. I call this cam the secondary work feeding cam.l.

Returning to Figure 8, there is shown in mesh with the worin wheel 66 aworm 74 on a shaft which, rotates in a fixed bearing and carries, at theouter side of the base, ratchet wheel 76, shown also in Figure A'pawl'77 drives the ratchet^76 stepv by "step and is operated to thatend by the work. driving mechanism through-a link 78 connected to `anarm of the work driving lever 14, a bellcrank lever having an arm 7 9yconnected to link 78, and a'second arm 80,

a link 8l connected to the latter arm, and

a pawl carrier 82 mounted to oscillate about the shaft 75 and on whichthe pawl is mounted.l The ratchet wheel 76 is interchangeable withothers and pawl'77 is adjustable on the carrier 82 accordingly, and theconnection of link 81 with arm 8O is adjustable toward and` away.fromfthe fulcrum of said armin order to adjust the machine to work onlgear blanks of different diameters and pitches.`

Whether Vthe primary work, feed cam-55` is put in operation depends on`whether, respectively, the sleeve 46 or the sleeve 44 is withheld yfromrotation.. and thelother sleeve left free to turn. Alternate arrest ofone sleeve and release of the other is effected by mechanism bothmounted on asrock-shaft 88 and eX- .tend toward respectively` oppositeysides of g the work driving mechanism ory the axis of the sleeves, withsuch anl angular spacing that, when said shaft isrocked in onedirection, the' stoppawl 85 isplacedin the path ofthe abutment84 and thestop pawl87 is moved out of the wayvof, the

abutment 86, and viceversa.'`

On the rock shaft k88 is an operating arm,

8,9 connected to a shift bar'90`which, when moved upward, releasessleeve 44 and arrests sleeve 46, and when moved downward effects thereverse condition. 4This shift bar is controlled by `.the timing cam 63and its p built in which the eEects described are obl tained in adifferentnumber of steps. yItis to be noted, however, that the angularextent of each rise on the secondary work feeding cam 73 is comprisedwithin a single rotational step of the timing cam, while between thesuccessive rises of the cam 73 are dwells fully as 'long rangularly asthe intermediate steps of the timing cam.

.It will now be understood-that when the work driving mechanism is inoperation, they timing cam is slowly given one 0f its steps.

of rotation by a succession of steps of the pawl and ratchet 77, 76 andgearing 74, 66,

while grinding cuts areL being taken in succession on the several teethof the work; a

dwell in the secondary work feeding cam 73 then passingunder the rack40. Vhenfthis step of cam 73 is completed the timing cani shifts therelation of the holding pawls'85, i105 87, the cam sleeve 44 is arrestedand sleeve 46 left .free to turn. The latter then drives theprimary work-feed cam `55, and said'.

cam, through arm 56, gea'rsegments 58, 59,

and pawl and ratchet 61, 62, advances thefllo secondary work. feed lcam73 while .a `rise thereof passes under the rack 40 andthe `latter iscaused toturn the work feed nut 26, by means of the pawl'and ratchet38,27, i115 to raise theformerabutment 1l. At the end of this step thetiming cam, which has been moved in unison with the work feed cam 73,

again reverses the relation ofthe stop pawls i 85, 87 and thexwork.driving mechanism is* again put in yoperationr toy cause anothergrinding, cut to the work- Thereafter the work feeding and 'work drivingmechanisms are operated (malt-ernation until the inalor finishingcut istaken.

During the timel when thework driving mechanism operates, the dwells ofthe secondary work feeding cam pass under the feed actuating rack 40.without causing any movement ofthe latter; `and whenk the work feed- .K

be.v taken von allfhe teeth of iso ' (Figure www ing mechanism is inoperation, the steps then given to the seeencla'ny' camg731f eausevthe"rises of saidf cani tofpass under the ifa-@l har and" displa'e thelatter. V'The anfreunt o termined' by thehei'ght of fthe eamrise-Whichpreviously` operated "the `reeel' nieehanis'ni. By changing* the,segments of' earn.' the length ofA each step'y of-'therfeecl may heVbelt froma pulley fastioirthetiriaini shaft '42 to an adjacent pulleyloose o lr'sa-i'cl4 shaft. 'p This shifting of the beltpis eceoniplishedunder the control ofthe timingl mechanism by the followingmeansf-A 'heltshipper' 92 .horizontal enclyvi'se-nioyahlerocl 94 (Figure leekeda with,a

1;) This @deesse 'through gee 915 on the; :frame the machine andeaI'jri'es; a oQllariQG between which ,anclsaidelug is conlthe fastpulley," a seeonl collar 99- on roflfv 94: is" Carried Beyond and?`iintfery p late hvliOO ('Figures land Q4) which isfheld upin*locking'positionhy Va springfpressedf plunger. 101" afil lifs'provi-deel 0f, a Stud Qreqere'lent proeef 1,03 '0115 the heb of the eserf6?. TheJPrQieQPvn 1:03 iS so positipned; that when thegcyele'ofltlie'ma- @bine @idea-has arrived @1t-@hemmt whereit displlaees latCli1100 andv release'sthe rod v9 4. y

Vthese articles, thlfe isi some variatibnhetaeen pieces iiitentllefl toyloethe same asl `tothe grqnnglufInginitially settingthev Work theAlatter Iniist he: gi'yen a eorreetangflilar relation/to the forrnei;since the y angtilar'distance ofthe toothlontliege'arlfirst to hehrouglit ta-,the glpinlingWheelfcleterniines the' amount eilt. Qncetth-e Work is'seouredto'thespinclle f iterentpostons.- v

fromJ thegafljaee'n distance away`- 'and shaftiuigl p y mentiu'in; to'stia-rt'- the; Carrelage! iii-the oppositie f* 'material'v ''romliftheaoesi oi'1v the teet for othen projections Whielr have to be slide;

all the teeth Will helgro'uncl rtol the same thickness -jwitlirl respectite" an. assumed center line' of each tooth'. y Een sosettnglftheyworlIlfljave yprov-Milled a locating inemberwhich orftheir equivalents,fispr'a'eti'eally ne'cessa'ry the f turnier o'eenpe's jangulairlyfwth.respect toethe `Werk slide -f when: the glatter isk iin! dif'- The vloeating` inem ed" on `a stud i105/ Whi'ehvextenlsfirom one end of lashatvlll anclisjeceentriefite-ythe shaft.' j -Sail is"'rotat'agloly'mounted in `a hearing 1,507' onf theVv upperzjencl eflfthef'slicle an@protrLides-j thereroin at :en'eenrlgawhereon risf-s'eeureclan eperatinggi e 1042 is` arrangedfte ove l 'f the ripper.' enel Offb@ 5336-5" ail-flri yf fcdiineetett tofo'r iN'orma-llytile eperatifi'igkarin` y108ivan'elE/leif' fi's3 the sidefaWay--iigom the ma'eli/inembase.A"W'l-len-f the slide' is at ether lower' Aendl :off lits eating alriir1042er@mythe-position; shown in travel the locating arno'issoinewhatremoyed l in Vthe.latteny isulessfthem;

lo ave; f rleasenjoit their medirection;

come-any tendency -whiohtl'ie Vdlnwing pulley;

shown"r in Figure# li tpthat shown inixllliglines 2 and* lQyWliereitifisaiirestiedliy: stpx 11111,k 'and tllejloeatirigileven 11941isthussshivftedlun- 'ofjth'eb'ase-.ff The serew stopzll'fbeanssonetheBefore- 'thef operating arm'.v has reached the stop 'llOand y latter armae`t`s, throngh the?y lbmiting` 1 'avian yaridstfo-p, tol meveltlheWorkfslicleinto ayprethe final: n1oyeinent:v of @the cl'eterriinecllpositio'm theI same trimef, the l New., whenthrworki'pieees'appliedlztolfw v v the' spindle'efthe' operating;fannoA of tli'ejnlo-veating 'deViceis-'brought tniftheposition r force holding its face `9 incontact with -the abutment, isrolled into the predetermined y positionfor setting of the work.v It matters not what this precise position is,provided .the gage is adjusted with reference l-to that position.Whatzis accomplished bythe lo- 'l eating means is the 'ability to p lacethe slide in lexact location, and inl the same location, when each newworkpiece is applied. The

1 capacity. for adjustment of the stop.110 en- ;,ables the locationtobechanged and graduationV marks 113 on its head, coacting with a ylstationary index 114, enable the shifting hof the'slide from lany fixedposition to be exi The facey 116 ofthe gage corresponds to a` actlymeasured and its re-location at a know distance to. lbe correctlyeffected. v

eating means justv described is a bai' 115 (Figures 2, land 14) mountedin a suitable holder land projecting at onev end to enter a spacebetweenadjacent teeth of the4 work.

rack'tooth face and makesy contact with the adjacent face of tooth 11'?of the work piece.

The gagegbar is secured by a set screw 118 in a holder 119 andthe latteris pivoted 'by a pin 120 toa bracket 121, which, in turn, is :adjustabletowardr and away from the work spindle on a guide 122. The guide, inturn,`

is angularly adjustable on a plate 123 which lsurrounds the worklspindle and covers the guide in its various adjustments.

ments ofthe bracket 121 toward and away (from` the spindle .are providedfor to accomend of the bearing sleeve thereofand'is secured to arigidpart of the work slide.

Topermit this angular Vadjustment of the guide 122, the latter is formedwith a curved lbase Vportion 124`and curved .slots 125, concentric withthefwork spindle.- Clamp screws 126 passing through said slots'in thebase 124 and screwed into the plate123 secure the Adjust- ,-modate :thegage to gearblanksV of-diiferent ldiameters.

n A clamp screw 127, passing through the brackety anda slot 128 in theguide, secures these adjustments.` -A- spring `129 stretched betweenabutments on the .bracket and on the'gageholder, respectivehly, normallyholds the gage out of contact with L'the work piece and in the positioni shown by dotted lines in Figure 14. f S

Then the gage is to be used, it is swung A forward into-a space of thevwork piece and may be made fast by tightening Athe pivot 120, the latterbeing. a screw mounted in a well known manner to'perm'it it to betightened or loosened so as to clamp or release ythe parttwhich turnsabout it.y Thereafter the work-piece is secured to the spindle bytightening the holdingy lnut 130.

By adjusting'v the position of the gage angularlyabout the work spindle,the workpiece maybe adjusted to control the amount of material to beremoved. In addition, a

The gage which cooperates with the lo-l fine-'and delicate vadjustmentmaybe given by turning the stopll() while the gageji's Y made fast tothe work slide and the work i pieceA is freey to turn on its spindle.--Such adjustment of thestop shifts the work slide and causes the .formerand the -workspindle to be rotated relatively to the work piece,

the latter being then held back by thegage.

erence to work'pieces having the `vmaximum amount'of material toA beremoved, rand is preferably such that when such a work piece kisappliedto the spindle las described a light cut will be v`taken in thefirst pass over thec grindingwheel.

- .Therangeof movement to be given to theformer-"abutment for,r feedingthe work betweenvsuccessive cuts, as previouslyrde- .The 'setting of thegageis. made with refscribed, is determined with respectto thesameavoi'k piece; that is, lone having the maximum amount` of surplusstock to `be `removed. Then the back stop 32, t'owvhichl the feed vnutl26 isvbrought back aftery the completion of each gear,- is set sothatthe 4'abutment -11 will be brought into the proper 'relation to theformer and fto the1 gage to f cause this light cut lto vbe takenin sucha work `piece 'inl the i'rstlp'ass. Thenthe amounts of rise the,severaly segments or lobes ofthe secondaryv work feeding cam 73 aredetermined `according to the amount f of stock to be fremovedxfromsuchfa work piece in order'to bring it .to a` final finished size. Thatis, the sum of the feeding steps given jbythesuccessive segmentsofLthecam will be,y great enough to` bring theformer abutment` tov theAHpoint at `whichftlhe', tooth being ground will have the -inalthickness.

It will be notedfromFigure2 thatthe face `ofthe tooth on thework piecewhich bears on the-gage face y116is opposite to that face of the toothwhich isacted on by the grindc ling wheel. Hence, a work piece on whichtheteethr are ofleiss than maximum thickness will, when set. as' justydescribed with reference to the gage. bevmore distant from the-grindingwheel when the first pass takes place, than oneof the greatestthickness.

'It is part of my invention to enable work piecesv havingteeth of-lessthan maximum thickness to bebrought'at onceinto grindtime taken for. awhole, series of cuts, or even two or more series, on the work may besaved.' To accomplish this enduit is necessary that the secondary workfeeding cam be rotatable independently of the timingmechanism, and thatthe work driving meansshould be disconnectable from the timingmechanism, so that thework maybe' brought into contact with the grindingLeimen;

wheel I- 'i'efo-'rey the timing mechanism f begins tol function. It isalsone'ces'sry as 'a safety measure to heiableto stop thefmafohine 'atany time, and to restart ie, an ,without ineens-gtire-{timing-iaee1fransma To serve these i irp'oses,v 'that'partfoiT`the eohn'e'eti'on fronti Lthe Work -drivingf meehanisni'to the timingm'eehanismwhieh Ihave heretofore A"des'eriio'ed as "a l:hell vcranklever living tvvo arnYsTQandf'SO, is made of two sefarate "arts, hoth-pivotd yrmftl'ie same fstuc 13H-ias shovvnjfurther in Figure 6; They'ari'n "80 jisprov'ided 4'With a lug 132 which overlaps arm 79,Whereloythemotion of the Work 'driving mechanism is posi tivelytransmitted to fthe patvl' 77 `in vthe driving movement 'of thelatter.Assoeiated rigidlvvvith arm() Vis. an -farm- 133, and a spring' 134 isvvrappedfarohnd the hub `of the; *lever 8041335 and engaged yat its.'ends Wi't'h the A"arms V79V -and 133so-fas" to. .canse arm 180 toollo'vv' 'armQon the return 'st-rohe but permit itslkheifng l1festrained'by 'superior 4force from so ffellvv-ing.'i :Airm' 133.has 'a `latchA'sh'cnllder 135Yon-the upper side of its outer end. Y

4A. leverf136 i's-mofunted: on a .pi-vot 13'? fandfhasialug-l'prvided`With a latch shoulder 139 "on its under side adapted to overliejandinterloelrwiththe shoulder. 135,

asslifown 'by.clottedylinesinf Figure 1, .A stud 140 is fearriedb'yfsai'dilever 136 and 4hears against` the collary `96.onthe V'loelt"shipper'rod 94.

vWith the movements of the mechanism the 133 oseillates between the full-line@,iposi-tio1r and the` ,dotted line lpo'sitionshown.fin.'FiguresylJandf 5, fthe associated zarms E-.and ,'79: heilig also ,oseillatedthrough :the same range of movement. In :the '-lovvermostv lzpositionof: "Lfrm .lybu-.t in no other position thereo,^its 'looking,shoulderf'f135r-niay 'he fpassedfover by theV lug 138 .of lever 136.Said armis-in.itsfloxvermost positionfatithe vmoment when thev stopmechanism -is `t-1.'i} :11: ed at.y the-fend or the grinding cycle,hythe--releasef-of-the belt shipper rod, as;previouslydescribed;- andvat that time the collar 96` on the shipper rod 94 throwsl the lever13.6 ,-toj thevdotted vline position, :its lug; then overlying the endof arm 1313" and Vvthe gshoulders 135Mand 139 becoming iinterloeked. Anymovement ot the Work Vdriving mechanism wvhieh new tahesplace ivvill'have lno e'ieet .on the tim'- ing mechanism.

, This is the-condition which eXSS ever ya. nevvv Workfpiece is-applied4tothe ma-y fchine. 1 When-fthepiece has been :gaged and set as;deserlibed', Ythe Operatori: Sets the' ehin'e in motion by Vpulling-theshipper rod to fthe right `in .Figure 1 byfmeans-:oithe head 98. If theWork 4doesqfmat Comeinto Contact fvvith thef grinding Wheel: rfhe firstapaise;thew operator. turnsfthefseeondary feed `rack bar.

cam 73. byfmeans 'of the hand operated shaft v arm and the-connection isagain made bef tween thevvork driving.meehanisml and the timingmechanism. It is to Vbe `understood that the operatoryeompletes thisConnection as ,soon as thetest carried iout vas above described `shovvsthat the Work .is far venougl'i advaneedto be ground. vIt may he gon thefirst pass over thefgrifnding lWheel or after the eedzmeehahism has.been advanced one, two, or. even more of -its1s'tep"s.. In case theteethv of the vvork piece shouldhel consider l ably thinnerfthan themaximum, mneh time is .saved in grinding the piece to iinished sizebecause all ,of the-prelnnrnary motions required with a gear havingteeth of maXimum .thickness are skipped.

The pavvl and ratchet drive betweenY the f fgea'r Wheels .66 and-67rpermits 'the feed mechanism to beadvanced by yhand-in thisaW-ay andenables `1t to befautomatieally connected with the timing meehanism asksoionas` .the

latter is put in operation. 'No particular care isneeded on the'part .ofthe operator in turningv the feed cam by hand, provided he vcompleteseac-h step of they feedv and carries the high fpafrt of `the 'ea-IhVsegment past the i Ifhe earriesit a litt-le too `far. no harm is.doneiheoause "of the'subsequent dwell in the -eam surface. andAtherfaetthat the -pavvh Whenad'v-aneed by the timing mechaN nism, will`pick up the cam and-'advance it -rthe remainder of the 4next partialrotation.

-For stopping the.y machine in. an temen genoy, Iy have provided a lever141 -pivo'ted to the 'frameat 142 and'havingfa.:projection 143 .adaptedto engage a trigger-144. The trigger-is pivoted `on a lstud 145 and hasav the lever 141roceupies the lposition shown in Figure 1i, but in orderto stop the machine instantly in emergency this lever is raised to the`position'shovvn in Figure 5, 'Where its projection :143 engages trigger144 andgdis- 'engages the latch 100 r from the belt shipper linger '-146overlying an extension 147.011 the `latch 100. Vhen `th'e machine isrunning,

rod 94. "Itisimportant at such times that 1 the timing fmeohanismshould.not be vdisconnected :from the Work driving mechanism, because if,'uponre-istarting the lmaehinathe `,operator should not thereafterimmediately disengage lever 13,6 from the 4disabling. arm 133 of`thetiming mechanism drive,"-the oor- -.-re,ctrelati on ofthel timingmechanisinto the .work driving ymeehanisnju wouldJoel vder: stroyed;altheugh the Work drvng'meehaiso nism would roll the work past thegrinding wheel, and indeX it after each pass, the tim-lr ing AmechanismwouldV remain inoperative and no further feeding movements., would fcourse of an emergency stop it will not interlock with the arm 133.

"of time. ance of the cutting action is otpartieul'ar They pivot 137 ofthis lever is carried by alink 148 which is hung from vapivot 149 on themachine frame. The pivot 137 is connected by a link rod 150 to the lever141 at the point 151. The lengths and positions of these parts, namely,links 148 and^150 and pivots 149, 137, 142 and 151, are all-so arrangedthat, when the emergency stop lever is raised to release the-beltshipper, the pivot 137 is moved laterally, and slightly downward..The lever 136 being then turned about this displaced pivot point bymovement of the belt shipper, its lug 138 moves in a lowered path inwhich it is obstructed by the end of arm 133, even when the latter is inits lowermost position, and will not pass over andlock such arm. Whenthe emergency stop lever 141 is released it will drop back nearly tovnormal position. The machine may then be started again by swinging thelocking lever .136 to its normal position (that shown by full lines inFigure 1), where it tends to stay until displaced in either vof the waysjust described, or manually.

It may be noted thatwhen the emergency stop lever 141 is in its normalor lowered position it rests against'a stop 152 and in that positionforms, with lthe vlink 150, a toggle linkage which holds the pivot 137immovable by any forcewhich may be applied thereto through the lockinglever 136.

In its turn the locking ylever may be re-v strained in its normal orinoperative posi- -tion by a suitably arranged spring or other yieldingwithholding means which will pre ventv accidental interlockingengagement with the disabling arm 133 while permitting engagementtherewith under superior force exerted by the shipper rod 97 when thelock 100 for said shipper rod is tripped.

By virtue of the locating means for the carriage, the gage for the workpiece, which is adjustably fixed to the carriage, and the means fordisconnecting the timing and feeding mechanisms :from the workdrivingmechanism, it is possibletomount work pieces on the machine in suchposition' that the lsubsequent automatic operation of the machine will`removey the amount of stock required to bring the pieces to finalfinishedform and dimensions; and to set up the'work piecey thus andbring it into ContactJ with the cutting tool with a vminimum expenditureThis time saving in the performvalue in view of the fact thatthe-conditions of this character of work,.in the automatic operation ofthe machine, require all of the teeth of the work piece to becarriedpast the cutting tool before any increment of feed movement isgiven tothework.

It is apparent, of course, that the setting ofthe work and operation ofthe machine as heretofore described results in the lfinishlto set up thework for the tirst grinding so that less than one-half of the totalamount ofV material will be removed then, leaving thek greater amount tobe vremoved [when iinishing the second side of the teeth. That is, inthe first cycle, the teeth` are ground on one side deeply enough tobring them to true Y form and then a little more Lmaterial is-cut away;in otherwords, to grind away a little more than enough to cleanup allofthe teeth on one side,leaving to the cycle of operation'performed onther other' side the task of bringing-the teeth to final finisheddimensions as well as true form. This is only a preferred practice,however, and is not obligatory, v i

The. practical necessity.V o1" the locating device which I havepreviously described is due to the' fact that the work carriage cannotbe depended upon to stop always in exactly the same positionl Iwhen themachine is stopped, althoughv the stopping Vplace may be nearly theIsame ,onv all occasions. The particular locating vdevice described isnot the only means which .may be used for the same purpose, but may beconsidered as a typical means and as representing generi cally any andall forms of such means.

An alternative device for the purpose, which is considered as embracedwithin the generic definition ot such means, consists in provisions formoving theoperating or impelling cam k13.to a given yposition whensetting up the work, for this will also bring oit the frame vwhichsurrounds thecam (see Figure '1),and into a hole 156 lin the cam (seeFigure 3) which comes within therange f ont the slot when the machinestops. Then by moving such insertedbar until it brings One way Ais tovinsert a bar through a slot 155 inthe partv up against one end oit' theslot a iXed locating point for the cam and consequently.forv

the carriage, is found. Another way yof so moving the eam as to obtainthe sameresult vconsiSt'Sfin turning the shaft 53 manuallyy byv a Wrenchor equivalent. device applied to the outer end of 'fsa-id shaft.; 'Asthis shaft i is made fast to the sleeve 46 and the latter is geared tothe sleeve 44, carrying the impelling cam I3- through the trainvconsisting of the gears 49, 48 andpinion 50, rotation of theshaftw'vill rotate the eaml The posiT tion to which the. cam is thusmoved isde-k termined by the stop paivl and that one of the abutments Seon the sleeve 46 which is adjacent to the paWl when themachine stops.

Thecharacteristics of they timing mecha' msm are such that when themaohinestops at the end oi' its; cycle, the pawl or dog 85 drops in thepath of. the abntments 84.`

Then, in accordance with the. presentfinvention,- the lowest part of thecam, When in engagement with the rroll 17 on lever 14:,

is slightly in advance of the engaging lo-v cation of the nearestabutment 8.4i with the stop paWl 85;. The machine naturally comes torest when 'the lowest part of the cam is beside. this roll. The relationoi: the abutment and stop p'aWl isthen'substantiaflly as indicated in'Figure l5. The manual rotation which' is now givento the shaft 53,. inorder to locatel the carriageA as justdescribed, turns lthe cam untilabutment 84 is arrested by the stop pawl 85. Thisl is an exactly defpiece is applied.

termined location and it causes the carriage, 1n turn, tobe placedv inan exact location, and in the same location'whenever a new Work Althoughin the have referred to the Work as a spurfgear, it

isto be understood that the same character of operations maybexperformed by machines having the'r same principles as che-reinbeor'eWell as the. specific machine element knownv as a spur gear.

Evidently reversals andv otherv modifica-` tions in the arrangement Vandstructure of the parts of the machine may `be made With-v in thespiritoif the invention', Wherefore it is to be understood that I do notlimt my claim for protection to the' details of the machine? -liereillustrated, and that the "appended claims are to be' construed asincluding such reversals and modifications Withinthe range' of ntheirl'equi'valentsLl l lVhat I claimy and desireto' secure by Let-V tersPatent 'isr g l. A generating machine of the cl'iaracter foregoingdescription I' setlforthincluding a reciprocating carriage,

a spindle. rotatable on said carriage, Vl'neans increments of feedmovement toy takev place inalterna-tion with a series. of reciprocatingmovements of; the carriage, a locating means for placing the carriagelina definite position,'and a gage mountedadjustably on the carriage andadapted 'to determinethe posi.- tion of a Work. piece. on said spindle.v

2. In a' generating machine having a base, a carriage. movable backand'forth on said base, a work spindle rotatably mountedon the carriage,a former-connected with the spindle, a complemental normally stationaryabutment arranged to yCooperate 'with said' former in giving a Vrollingmotion to the spindle when the carriage is, so moved, an adjustablelocating member arranged tov cause placement of the carriage in givenlocation en the base, and a gage mounted OI.1 the carriage and arrangedto make Contact with il Par-t oi a workpiece to .cause placement of theWer-k piece a ive-n angular relation to the for-mer when e carriagey isin suchfposition'. l i y K. f

V3. A generating machine of the character set ortlncomprising ab'ase, aWorkcarriagev movable back and forth on, said basen; a work spindlerotatably` mounted on said carriage--V complemental elements @Qlfnec'tedto said 1700 tol-impart rolling motion tothe spindle When;

' spindle and base respectively, and arranged the carriageiis thusmoved,- mechansm for so movingY said carriage, automatic mec-hanism forshiftingone of: Said v complemental' elements, al timing mechanismconstructed t0' cause alternatezaetion ofthe carriage driving means andsaid automatic shi-ftngmechanisl-n, said last-named mechanism:includinga driving. impeller positive in one direction only, and manuallyOperable means for pro.'-y pelling the shiftingv mechanismindependent 1yof its automatic impeller. e 4l. a gear generating machine having-aformer and abutment, one of which is arranged to.; rollA upon the other'for giving-v rolling movement toy a; Work piece, said abutment beingmovable independently of rollingY action so asi tog'ive a feedingincremaentv oi`r rotation to the Work piece,` an automatic fdlg'mehasnism for iso-movingifid abutment including a driving Vpart-,ivadriven part and a: propel-lingconnecton 'between said parts arranged. totransmit motion from the drivingpfa'rtto the drivenpart and to permitindependent movementin the same, (li-f recti'onof the. latter'ahead ofthe former, 'and means for enabling the Ydriven part to,- be drivenindependently by manual opera-timal 5.1.` In a gea-rygenerating-zmaehine, a-utomatic gear rolling: mechanism including ,a

carri-age, a spindle rotatably mounted onthe V carriage, a'formerconnected With the spindle, and 'an abutment arranged to Vcauserotation'of the former When'the carriage isk moved, driving mechanismfor the carriage, said abutment being'shiftableto change the angularpositionof'the formerand spindle independently of V theV carriage,automatic mechanism for so4 shifting the abutment,

timing mechanismdriven alternately by the carriage driving Vmeans andthe-abutment shifting mechanism, respectively', for causing each of theother mechanisms: to become operative exclusively #in alternation, and

means for interrupting the connection betWeen'the carriage vdrivingmechanism and vthe timingmechanism, -Whereby to permit-a 1 preliminaryadjustment of the Work.

' 6. A' gear generating machine comprising a carriage, a rotatable Workspindle mounted onV said carriage, a former-securedto the j Workspindle, an abutment cooperating With the former tooscillate thespindleWhen thel j carriage ismoved back andfortlnautomatic i Work drivingmechanismk for moving the carriage, automatic abutment shiftingimechanism. for displacing` the abutment togive a feeding movement totheWork spindle, tim-A v ingmechanism constructed and adapted to put saidWork'driving mechanism in operation, at the same time disabling theabutment shifting mechanism, and toV put said abutment shiftingmechanism into operationV "at the Sametime. disabling the `Work ydrivingmechanism, means'by Whichthe Work driving mechanism andthe abutmentshifting mechanism, in turn,drive saidtiming'mechanism, lmeans fordisabling Vthedrive from the -Work feeding 'mechanism to the timingfrniecliavi'iism,y and means for manually shifting f the abutmentindependently of the auto-inatic mechanism for that purpose.

7. In a gear generating machine having a base,V aback and forth movingwork car- ]riage, a spindle rotatably mounted on the carriage` a formersecured to the spindle and a complemental abutment for rotating thespindle when the carria e is so moved, an-

adjustable locating mem er'engageable With the'carriage and base forplacing the carriage in a given position ,on the base and shifting it bymeasured amounts, a Work gage secured to the` carriage adapted to con-Vtact with a Work piece-on the spindle and being adjustable angularlyabout the spindle, automaticV mechanism for driving the carriage,automatic mechanism for, shifting the abutment to feed the. Work, timingmechanism for putting each of thepreceding mechanisms alternately :intooperative condition,

at the same time puttingithe other of'said mechanisms outY of action, adisconnectable driving connection from the carriage operatingmechanism-to the timing mechanism,

and a transmission .connection in the abutment shiftingmechanismi-Whichis positivel only in the feeding direction and is yieldable` to permitadvancement of the abutment beyondthe mechanism for automaticallyshiftings.' Y

L8. In a'generating machine of Jthecharacterl described, a base, acarriage movable backY and forth on` said-base, a 'locating means. forsetting the carriage in a given position on the basenearone end ofits'travel, said:

locating means comprisingan arm, a shaft i rotatably mounted on thecarriage and Vhaving an eccentric stud on which said .arinis pivoted, asecond arm'associatedTvvith-vtheY first-namedarm and Vhavingv a stopmember. adapted tobear on the carriagewhen the first arm-bears on anadjacent part ofthe Y base, and an operatingarm secured to the shaft andoperable to rotate thel latter so as 'to bring the aforesaid arms intoand out of operation. i i y9. In a generating machine ofthe characterdescribed', a base,V acarriage movable back and forth on said base, andmeans` for locating the carriage in a definite position on the basecomprising connectedarms,r one of which is adapted to bear on a surfaceY,

r*of the base VandY thel other to lbearon ya surjface of the carriage,andA a movable mount.

for said armsope'rable to place them inzand outv of operativeposition'.l v Y l 10. Inl a generating machine-of the characterdescribed, va base, a carriage movable lon said base, and a carriagevlocating means! comprising connected arms and a mount on ,-Whichk saidarms aref-rotatably supported,-

said mount being shiftab-le toput said arms. into a positionv Where oneof lthem is adapted to bear onthe carriage and the other is adapted `tobear jon the base, one ofrsaird-y ino llla') arms having anv adjustableVstopV through,

the adjacent member being adjustable relativelyto the other arm, wherebyto eifect an adjustment in the positioning ofthe carriage.

l2. In a scribed having a carriageq a Work spindle mounted on thecarriage, a former connected to the Work spindle and a lrelativelystationi ary abutment against Which the former acts,v` a gage mounted onthe carriage With provision for adjustment angularly about the. axis ofthespindle and mounted to coact With a peripheral projection'of the Workpiece,

and amount for lsaid gage constructed to i machine of thecharacter ,dein ofthe carriagey at a fixed point in its travel,

.said'method consisting'inlocating the gage in suchangular relation tothe-former that placed on `the, spinilleY in locating engage- *iinentwith thegagatlie carriage then being in a given position, such `workpiecewill be abutment combinedfwith a grindingwheel` Y d nlock. andVshipper being so arranged that the movement 'of the shipper tostop-tliemachineV applied. thereto incorre'ctly-related toY the cuttingtool' tovbe acted on by thelatter when rolled past it;r

then placing similar work pieces, but 'hav-V Ving less stock ltoberemovedfon 4the spindle with the same setting `of the gage andcarriage, making atest pass ofthe worlrover the `cutting tool,andthereafter manually displacing theabutmentand making a further testpass until theworlris brought to the'ad.

justment wliereit is acted lon by theeutting tool.V f 22.l In a gear.generating machine-having aY carriage, a AWork spindle, aformerfandilan and farrangedtocause such combined movee `ment ofarwork'pie'ce xed tothe spindle,-

whenrthe'cairiageis moved,1that atooth face yof the work VpieceY rollsover the face-of the grindingwheel, fa step.` by stepv feed mecha-fnismfor 'shifting'.the abutment so4 as to ad-k Y vance the workrelativelyV to the grinding wheel, an automatic driver for said feedYmechanism, a power transmitter 'between Vsaid driver and mechanism-whichis positive only in the forward direction, and a'manually operateddriver: for said feed mechanism transmitter. 'Y

23.v Ina generating machine ofthe characterset forth, a .workydrivingmechanismfa timing mechanism, Va trai'iismission mechanism fromsaid worlrdriving mechanism toY thetiming mechanismand including atrans'- missionmember which Vis positive in one. dii rection only andV afyieldable connection through which movement in thek opposite direcitionis transmitted, there being a detei'itv element onv thepower-receivingpart of'sad transmission mechanism, combined with-an`automatic.'means for stopping the machine, and a locking memberoperable by saidsto'p pingg'meansand arranged to interlock vwith saidY'detentelement to prevent .actuation of the timing mechanism when themachine is' I agains'tarted.

a machine -r `of fthe character der-AA sc ibedthe combination,withVaVwork driv-Y ing mechanism, of atransmission memberl 'ydri'ven therebyr'and l,including .aY driver, a'

lower are arranged to vtransmit jmotion .in

the opposite direction but to yield y.when the follower is'jarrested,adetent connected to i the follower and jaja loclcoperable to withhold dvance VofV said power` follower and ajspring,which driver and fol.-

` said detent when., the .followerjlapproXi-j mately at the endof/thefmovementv given by the positiveaction of the .driven f 25; In amachineofjthemharacterdef scribed thel combination .with a: Work drivingmechanism, :Y of a vvtransmission"V Vmember driven therebyandi'ncliiding a driver, a

followerfand a spring, which driverandfollower'are arranged to' transmitmotion in the `positive action *of the idrivei,V said flock beingcombined Withia movablebelt shipper; alocl foiflioldingsaid shipper inthe posi?.

tion Whichcauses the macliineto run, andV an Vvautomatic]ftiip forcausingsaid-f shipper to stop the machine "at the Vend of thecycle, the

causes arresting engagement ofthe lool; with said detent.v Y l' j .kf r

'26( In a gear generatingrmachine', `an automatic Work drivingmechanism,V anautomatic work feeding .'mechanism, fanV auto-i matictiming mechanism* constructed Vto e0.. mately atthefendof themoveinentgiven by I cause alternate operationvofyeachof the preceding mechanismsinl turn and with si-Y multaneous'intermission of the other mech-'anism,l an automatic stopping mechanism j for stoppingrthefmachine, tripoperated 'by the .timing mechanism Yffoil- {causing acf`r ytiia'tionvofsaid stoppin'gmechanism, di-iv Y ing connections from thel workdriving'inechariism'to the timing mechanism includ?V ing complementaltransmitting and follow# ing members which are 'positive in onedire`ction onlyand al springwhich isarranged tov transmit motion.r inthe opposite direction,

Va* detent associated with said following member, and a'lockarranged'toengage said iio detent and prevent movement of the follow;Y

ving member through Vsaid spring Whenthe means is automatically Ymachine stopping actuated.

27j. In a1 gear'. automatic vwork; driving generating machine, "an

'inec'hamsm',Y van automatic worlrffeedinglmechanism, an lau` tomatictimingzi'nechanisin constructed toV t cause alternate operation of`reach ofthehpre Y ceding mechanisms lin tui'nland in simul tane'ous.intermission ofthe 'other mechan ism, an automatic-stopping mechanismfor] stoppingthe machine, "atrip operated i by the timing mechanismforcausing 'actua-Y tionk ofl said i stopping mechanism, {drivingconnections from 'theivork-driving iii'echaniV ismuto the timingmechanism includingcomvplemental transmitting and foll'owing'smem'z-Ibers ,which are `.positivem one directio only and a .Spring whieh isarraneelte-treeem-t motion .the eppeefe direct assaeated with aa-idsllewiee einher., .and a leek arranged te `reni-ieee' said detent mdprevent movement of the Afollowing member .through said .Spring whenthemaehne step..-

rne Ineens ie eutemetiealr tripped-,s the said members normally holdingthem together and transmitting motion in said other direction, a detentarm connected with said following member and movable simultaneouslytherewith, a pivoted locking member adapted to overlap and interlockwith said Larm when the latter is at one extreme of its movement, amachine-stopping means including a laterally movable member engaged withsaid pivoted locking member in a manner to swing the same into positionfor interlocking with the detent arm when said member is displaced, ashiftable fulcrum for said locking member, and' a manually operatedtripping means for said machine-stopping means, connected with lsaidfulcrum to displace the latter whenever the former is operated to stopthe machine, said ulcrum bein guided to move ina path such that upon thelocking member being then displaced by the machine-,- stopping means itisobstructed by the detent arm and prevented from interlockingtherewith.

29. In a generating machine, acarriage, a l

work spindle rotatably mounted on the caro riage, and a gage mounted onthe carriage with provision for placement in position to locate a workpiece angularly on said spindle, and to be withdrawn from its locatingengagement with the work piece. Y

30. In a generating machine, a carriage, a work spindle rotatablymounted on said carriage, means ttor giving a generating motion to awork piece mounted on said spindle, which Vmotion is compounded ofdisplacement of thel carriage and rotation of the spindle, combinedVwith, a gage mountedl on the 'carriage and adapted to obstruct aperipheral projection on the work piece, and provisions for withdrawingthe gage from suoli relation to said projection.

31. In a generating machine, a carriage, a work spindle rotatablymounted on the carriage, and a gage mounted on the carriage lwithprovision for placement in posi- 9.11, keten? *i051 110 lpeate awerk-'piene ensalada ensei@ eliidla and te ylee heli-fawn ite 19:'`rerfenis engagement w1 ,t'l .tble'werlk "Piece, 11,1 lentille' withmfeaee" `for locating, .the 'e :in la given residen.. Y #generaties eine,of ,the character Set ,ferthfeolm i s'lga bese, a earrerreeip#'iteleateble the 0.11,"21' Werkspindle, Je .fermer eenneeted with gsite]Spindle, all` abutment .eeereratve 'with Seid fennel, rotatable vcuttingtool arranged on a 'work peee meente@ 0.1.1 "Seid spindle? Seid nele,leerte beine ,eeepeiatvey'arraiieede-nd- .01"- ganized to' eEectrelativewrolling motions between the work piece and the tool; means for'locating the carriage in a definite position with respect to the base insetting up the work, and a gage for the work piece arranged to determinethe angular relationl between said piece and the tormerwhen the carriageis so located. v- A 33. generating machine of the character set forthcomprising a base, a carriage reciprocatable thereon, a work spindle, aformer Vconnected with said spindle, an abutment co'- operative withsaid former,` a rota-table cutting tool arranged to act on a work piecemounted on said spindle; said elements being cooperativi-ely arrangedand organized to et- ,fect relative rolling motions between the workpiece and the tool, means for locating the carriage in a definite'position with re spectto the base in setting up the` work, and

a gage mounted with provision for angular adjustment about the axis ofthe work spindle relatively to the Vformer and having an element adaptedto be placed in gaging contact with the work piece when the carriage isso located.

34. In a generating machine 'of the character set forth, havinga/carriage, a work spindle, a cutting tool, and mechanism for eiectingtra-nslative movements of saidfcarriage and rolling movements betweenthe work spindle and cutting tool, work setting means comprising a gagefor the work piece and a locating vdevice for the carriage,cooperatively arranged to determine the angular relation ot the workpiece to the tool when the carriage is in a given position.

35. In a generating machine ot the character set forth, having acarriage, .a work spindle, a cutting tool, and mechanism for effectingtranslative movements of said carriage and rolling movements between thework spindle and cutting tool, work setting means comprising a gageangularly adjustablefabout the axis of the work spindle and shiftableinto and out of gaging relation to the work piece, and a locating devicefor the carriage. 36. A acter set Jforth comprising a base, a carriage,a work spindle, a generative cutting tool,

generating machine of lthe chan'v

